Does dual camera recording support slow motion on iPhone?
No. A dual-camera recording runs both cameras at a fixed 30 frames per second, and there is no Slo-Mo setting to switch either one into. That is not a missing checkbox somebody forgot to add — slow motion needs a genuinely different kind of capture, and a session that is already running two cameras at once does not have the room left to spare for it.
The rest of this is about why that is true, what slow motion on a phone is actually doing under the hood, and what to shoot instead when a particular moment really does need it.
What makes footage slow motion in the first place
Slow motion is not a playback trick applied after the fact — it starts at capture. A camera shooting in Slo-Mo records far more frames per second than the video will ever be played back at: 120 or 240 frames a second is typical on an iPhone, against the 30 frames a second a normal video plays at. Play those extra frames back at the normal rate and the same one second of real time now stretches across four or eight seconds of video, with enough real frames captured in between to make that stretch look smooth rather than jerky.
That is a specialised capture mode even for a single camera. The sensor, the image pipeline and the file it writes are all doing more work per second than an ordinary recording, which is why the stock Camera app treats Slo-Mo as its own mode rather than a setting you leave on by default.
Why a session already running two cameras has no budget left for it
A multi-camera session does not let each camera behave independently. Every camera in it has to run a format that is explicitly flagged as multi-cam capable, and the combined cost of everything running at once — both camera streams, the real-time compositing pass, the encode — has to fit inside one hardware budget for the whole session. A high-frame-rate format is already an expensive one-camera format; putting two of them in a session together, on top of everything else a dual recording is already paying for, is not a small ask on top of what a single 30fps stream costs, it is a multiple of it.
That is the reason DualCam's capture settings are 720p and 1080p, and why both of them are locked to 30 frames per second regardless of which one you choose. There is no faster option hiding in a menu somewhere — the format that would provide one is not a format a multi-camera session is able to run in the first place.
Slowing a normal dual-camera clip down afterward
A regular video editor can slow any clip down, dual-camera footage included, the same way it can trim it or add music — that part is ordinary editing, not something specific to dual-camera video. What it cannot do is give you back frames that were never captured. A clip shot at 30 frames per second has thirty real frames for every second of footage, and stretching that across more playback time means the editor has to manufacture the frames in between, either by holding an existing frame for longer or by guessing at the motion between two frames it does have.
That manufactured motion holds up fine for a small slowdown and starts to look soft or stuttery the further you push it, especially wherever something in frame is moving quickly. It is a usable trick for a gentle emphasis, not a substitute for footage that was actually captured at a high frame rate.
If a moment genuinely needs slow motion, shoot it separately
When slow motion is doing real work in a shot — a splash, a trick landing, the exact instant something breaks — the more reliable approach is to give it its own take. Shoot that specific moment with the stock Camera app in Slo-Mo, on whichever single camera actually needs to be slow, and shoot the dual-camera part — your reaction, the narration, the two-camera framing — as a separate normal-speed recording. Combine the two afterward in an editor, the same way you would drop in any other piece of footage.
It costs an extra take, but it means the moment that needs slow motion gets a capture mode built for slow motion, and the moment that needs two faces at once gets a session built for that, instead of asking one mode to do both jobs at once.
Common follow-up questions
Can I turn on Slo-Mo while recording the front and back camera at the same time?
No. A dual-camera session has two capture settings, 720p and 1080p, and both are locked to 30 frames per second. There is no Slo-Mo option to switch to inside a simultaneous recording.
Can I just slow down a dual-camera video afterward in an editor?
Yes, any video editor can slow a dual-camera clip down the same way it slows down any other video. It will look softer the more you push it, though, because the editor is stretching thirty real frames per second rather than playing back footage that was actually captured faster.
Is there any way to get true slow motion and a dual-camera shot in the same video?
Not from a single take. Shoot the slow-motion moment separately with the stock Camera app's Slo-Mo mode, film the dual-camera part as its own normal-speed take, and combine the two clips afterward in an editor.
Want to just do this?
DualCam records the iPhone front and back cameras at the same time and writes one finished MP4 while you shoot. Free, no account, no ads, nothing leaves the phone.